Objectives: The overall goal of this project is to maximize the health, social functioning, and quality of life of women Veterans with posttraumatic stress disorder (PTSD) who have experienced military sexual trauma (MST). The specific aims of this randomized controlled trial (RCT) are to evaluate the effectiveness of a trauma-sensitive yoga intervention designed specifically for women who experienced sexual trauma as compared to a gold-standard PTSD treatment, Cognitive Processing Therapy-Cognitive, to 1) treat PTSD and its co-morbid symptoms of chronic pain and insomnia, 2) improve social functioning and quality of life, and 3) reduce the biological and psychophysiologic responses associated with PTSD in women Veterans who experienced MST. Research Plan: This proposed four year RCT is the next step following our NRI Pilot Study (NRI 12-417) in which we demonstrated the feasibility of recruitment, retention, randomization, intervention implementation, and data collection, including biological and psychophysiological data. Women Veterans seeking treatment for PTSD who report chronic pain and insomnia will be recruited from the Atlanta VAMC Trauma Recovery Program Women's Trauma Program. Participants (n=210) will be randomly assigned to trauma-sensitive yoga (10 weekly sessions) or Cognitive Processing Therapy-Cognitive (12 weekly sessions); both intervention protocols are data-driven. The target enrollment sample size is 210, with a target final sample of 100 or more. We are conservatively allowing for 50%-60% retention, based on pilot study results. Methods: Data Collection: Data will be collected at four points, baseline through 3-months post- intervention. We will include self-report, clinical assessments and biologic and psychophysiologic markers as outcome measures. Specific outcomes include PTSD symptom severity, chronic pain, insomnia, social functioning, quality of life, cytokines (IL-6, IL-10), C- reactive protein, dark-enhanced startle, and heart rate variabiliy. Data Analysis: Comparisons between the groups at baseline will be run using t-tests, Mann Whitney non-parametric tests, and chi-square tests as appropriate. Multilevel mixed models (MLM) will be used to analyze the differences between the groups over time. MLM adjusts for attrition (missing data) over time and applies appropriate correlation structure between the time points. Clinical Relevance: Women Veterans experience MST and PTSD at alarming rates; consistently reported prevalence rates for both among VHA patient samples are 20% or more. MST and PTSD put this population at risk for significant physical and mental health symptoms, including chronic pain, suicide, and negative health behaviors. This RCT may provide sufficient evidence to support an innovative, complementary and alternative PTSD treatment for women Veterans who experienced MST. The positive effects of reducing distressing symptoms and PTSD-related psychophysiological stress would likely improve social functioning and quality of life and minimize the significant medical consequences of PTSD in this population. This new, evidence-based PTSD treatment could supplement existing evidence-based PTSD treatment modalities. Clinical guidelines for this innovative intervention based on evidence from this clinical trial could be disseminated to and implemented in VA Medical Centers nationwide.